[Dehydroepiandrosterone metabolism by Epidermophyton floccosum]

Steroid hormones may be relevant for the fungus-host relation in dermatophytoses. In contrast to most other hosts of dermatophytes, humans are characterized by a high cutaneous concentration of the adrenal androgen dehydroepiandrosterone (DHEA) and its sulphate (DHEAS). To investigate whether the strictly anthropophilic dermatophyte Epidermophyton floccosum can metabolize this steroid hormone, cultures of E. floccosum were supplemented with DHEA. After 5 days of incubation the steroids in the culture supernatants were extracted and differentiated by gaschromatography and massspectrometry (GC-MS). The results show that a nearly complete metabolization of DHEA by E. floccosum leads to the formation of multiple new steroids/metabolites some of which have not been reported before. Therefore, this fungus could possibly mediate the hormone regulated cutaneous defense mechanisms of the host by an intraepidermal metabolization of DHEA.